Stand just in front of T. Volley the ball on your forehand crosscourt onto the front wall near where it meets the sidewall. Take the next shot backhand crosscourt, and repeat. Try to hit the ball so that it comes right back to you. Use quick hands, short backswing, wrist when needed. (alt: hit every other ball straight off frontwall, sidewall)When you can do this drill comfortably, you look like a pro.